Year Measure 1990 0.02786 1991 0.02469 1992 0.02512 1993 0.02877 1994 0.02739 1995 0.02321 1996 0.02403 1997 0.02091 1998 0.02052 1999 0.02 2000 0.0204 2001 0.02046 2002 0.02104 2003 0.0257 2004 0.03014 2005 0.0286 2006 0.03005 2007 0.02076 2008 0.03643 2009 0.02957 2010 0.03396